My male best friend said he regrets knowing me?

Don't call him, text and explain. That way you get to say everything you want without interruption. If you want to maintain the friendship tell him that first off you were only joking about telling the person but they didn't let you explain and that you are sorry you maybe took it a bit too far as a joke but that his comment of wishing he had never met you has really hurt you and that you are struggling to get past it. If he messages back and says I am sorry I said it out of anger and didn't mean it then clear the air and move on, if he doesn't apologise for it then just let the friendship go. 

Don't call, don't text, don't do anything. Let him call you when he feels like talking . If he doesn't then just deal with it, move on and shake it off.

I think you both need to mature and grow up a bit, before you try to handle being in a relationship. You didn't give your ages, but from your description, it sounds as if neither of you are over fifteen.

Clear the air up with him. If you're hurt that when he said he regrets knowing you then tell him how you really feel about the situation. As they always say, "there are two sides to a story". Understand from his point of view and he'll probably listen to yours.

The fact that he was even calling you to “clear the air” shows maturity on his part. Sometimes joking around can lead to actually losing a friend. 

(Proverbs 17:17) A true friend shows love at all times And is a brother who is born for times of distress.

Call your friend and clear the air.

It wasn’t a very funny joke to begin with. Apologize and grow the **** up next time! 

Write him a letter, buy a stamp and post it to him. That might make him take seriously the apology I hope you'll be putting in writing.  He, seriously, needs to know that he can still trust you.

That happened to me once. Then I realized that I shouldn't have even joked about something like that because it takes the sense of "This only stays between u and me" away, immediately. I know that was a joke, but as soon as you said it, it bursted that bubble. 

It was all your fault.  Id say you should stay out of his life, since he wants no part of you.  

If I'm being completely honest with you; That wasn't a very funny joke to begin with. I think that you should apologize to your friend and admit to them that you were in the wrong. If they don't wanna be friends moving forward after your apology, then so be it. But if they really were your best friend, then chances of them accepting you back are pretty decent. However, you can't just sit back and wait for him to make the first move, if you want something, you have to go and get it yourself.